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    <title>Document</title>
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<script>
    // 每次的结果都打印
    // var sum=0;
    // for(a=0;a<=100;a++){
    //     sum+=a;
    //     console.log(sum)
    // }

    // 只打印最后的结果
    var sum=0;
    for(a=0;a<=100;a++){
        sum+=a;
    }
    console.log(sum)
</script>
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